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2. Idem, in ?Extractive Metallurgy of Aluminum?, Vol. 2, (edited by G. Gerard), Interscience publishers, New York (1963) p. 487.
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4. W. E. Haupin,J. Metals 23 (1971) 46.
5. W. S. Siraev, D. V. Forsblom and D. Ya. Khalpakchi,Tsvet. Met. 49 (1976) 33.